RF signal strength measurements can be used to estimate a location of an RF receiving device within a broadcast area. The location of the RF receiving device may then be used to provide a number of services to a user of the device, including navigation, location-based advertisements, etc.
Many methods of RF localization rely on constructing a database of RF signal strength measurements for which the positions within a RF broadcast area are known, and estimating a location of a device using RF signal strength measurements provided by the device and the information in the database. For instance, estimating a location of the device within the broadcast area may be performed by interpolating the known locations in the database with the newly acquired RF signal strength measurements.
In practice, providing an accurate estimate of location may require a database having a large number of RF signal strength samples that are correlated with known locations, and/or may require re-sampling of a broadcast area to account for changes within the broadcast area. For instance, if the broadcast area is within a store, changes to the interior of the store can degrade the accuracy of location estimates that utilize an out-of-date database. In addition, the desire to provide a more accurate estimate of location of devices in a broadcast area may require an exceedingly large number of samples for the database, which can be time consuming to collect. Thus, there is a need to improve location estimates within an RF broadcast area that do not rely upon creating and/or maintaining a database of a large number of RF signal strength samples and their correlated known locations.